Traditionally, cell sites are constructed using commercial power from a utility as the primary source of electrical power. Telecommunications power systems include backup power arrangements to ensure continued power in the event black-outs and other disturbances in the commercial power grid. To accomplish this, many facilities use a diesel generator. The diesel generator is then backed up by an array of valve-regulated lead-acid (VRLA) batteries. The combined arrangement—the AC electrical utility receiving equipment, diesel generator, and VRLA batteries—are all separately installed at a site. This takes up a considerable amount of space.
These conventional systems can be time consuming to install as each component must be engineered and installed separately. This is because each site has its own restrictions so the layout generally has to be tailored to the individual site, driving up engineering and installation costs.
Further, when a site's BTS and power requirements increase over time, the engineering decisions become complex. For example, the engineer must decide whether to augment or replace the existing equipment. Finding equipment to complement the existing equipment is difficult, due to space limitations and lease agreements with the land owners.